Deteriorating air quality in China has created global public health concerns in regard to health and health-related behaviors. Although emerging environmental regulations address ambient air pollution in China, the level of enforcement and long-term impact of these measures remain unknown. Exposure to air pollution has been shown to lead to multiple adverse health outcomes, including increased rates of heart disease and mortality. However, a lesser-known but increasingly significant concern is the relationship between air pollution and its effects on outdoor exercise. This is especially important in China, which has a culturally rooted lifestyle that encourages participation in outdoor physical activity. This article evaluates the intersection of air pollution and outdoor exercise and provides a discussion of issues related to its public health impact in China, where efforts to promote a healthy lifestyle may be adversely affected by the ambient air pollution that has accompanied rapid economic development and urbanization.

Background: Temporal interference (TI) stimulation is a novel technique that enables the non-invasive modulation of deep brain regions. However, the implementation of this technology in humans has not been well-characterized or examined, including its safety and feasibility.Objective: We aimed to examine the feasibility, safety, and blinding of using TI on human participants in this pilot study.Materials and methods: In a randomized, single-blinded, and sham-controlled pilot study, healthy young participants were randomly divided into four groups [TI and transcranial alternating current stimulation (tACS) targeting the right frontoparietal region, TI-sham, and tACS-sham]. Each participant was asked to complete N-back (N = 1 to 3) tasks before, during, and after one session of stimulation to assess their working memory (WM). The side effects and blinding efficacy were carefully assessed. The accuracy, reaction time (RT), and inverse efficiency score (IES, reaction time/accuracy) of the N-back tasks were measured.Results: No severe side effects were reported. Only mild-to-moderate side effects were observed in those who received TI, which was similar to those observed in participants receiving tACS. The blinding efficacy was excellent, and there was no correlation between the severity of the reported side effects and the predicted type of stimulation that the participants received. WM appeared to be only marginally improved by TI compared to tACS-sham, and this improvement was only observed under high-load cognitive tasks. WM seemed to have improved a little in the TI-sham group. However, it was not observed significant differences between TI and TI-sham or TI and tACS in all N-back tests.Conclusion: Our pilot study suggests that TI is a promising technique that can be safely implemented in human participants. Studies are warranted to confirm the findings of this study and to further examine the effects of TI-sham stimulation as well as the effects of TI on deeper brain regions.

Age-related decline in dual-task (DT) performance is closely associated with falls in older adults, posing a significant public health concern. Virtual reality (VR) training has emerged as a novel intervention to enhance motor-cognitive integration, yet its effects on dual-task performance require systematic evaluation. The purpose of this systematic review and meta-analysis was to assess the impact of VR training on dual-task performance in older adults. Following PRISMA guidelines, we searched four databases for randomized controlled trials (RCTs) evaluating VR training in adults aged ≥ 60 years. Inclusion criteria required comparisons between VR training and non-VR control groups, with outcome measures including dual-task cost (DTC), dual-task timed up-and-go (DT-TUG), DT gait parameters (speed, stride length, cadence), and DT cognitive performance. Methodological quality was assessed using the Cochrane Risk of Bias tool, and meta-analysis were conducted using RevMan 5.4. Twenty-one RCTs (935 participants) were included. Meta-analysis revealed significant improvements in VR groups for DTC of gait speed [SMD = -0.32, 95% CI (-0.57, -0.07), P = 0.01], stride length [SMD = -0.58, 95% CI: (-0.90 to -0.26), P < 0.001] and cadence [SMD = -0.32, 95% CI (-0.64, 0.00), P = 0.05]. DT-TUG time decreased significantly [SMD = -0.54, 95% CI (-0.89, -0.19), P = 0.002]. VR training also enhanced dual-task gait speed [SMD = 0.38 95% CI (0.03, 0.73), P = 0.03] and stride length [SMD = 1.15, 95% CI (0.81, 1.49), P < 0.001]. Subgroup analyses showed VR brought more notable improvements for MCI and PD patients. For VR interventions, durations over 1 h per session, more than 4 - week duration, and 3–5 sessions per week yielded better results. Yet, no significant improvements were observed in other DT aspects like cognitive reaction times and rapid gait speed. VR training effectively reduces DT performance decline in older adults, particularly by lowering DTC and enhancing functional mobility, supporting its potential as a fall prevention strategy.

Background: Temporal interference (TI) stimulation, an innovative non-invasive brain stimulation technique, has the potential to activate neurons in deep brain regions. The objective of this study was to evaluate the effects of repetitive TI stimulation targeting the lower limb motor control area (i.e., the M1 leg area) on lower limb motor function in healthy individuals, which could provide evidence for further translational application of non-invasive deep brain stimulation. Methods: In this randomized, double-blinded, parallel-controlled trial, 46 healthy male adults were randomly divided into the TI or sham group. The TI group received 2 mA (peak-to-peak) TI stimulation targeting the M1 leg area with a 20 Hz frequency difference (2 kHz and 2.02 kHz). Stimulation parameters of the sham group were consistent with those of the TI group but the current input lasted only 1 min (30 s ramp-up and ramp-down). Both groups received stimulation twice daily for five consecutive days. The vertical jump test (countermovement jump [CMJ], squat jump [SJ], and continuous jump [CJ]) and Y-balance test were performed before and after the total intervention session. Two-way repeated measures ANOVA (group × time) was performed to evaluate the effects of TI stimulation on lower limb motor function. Results: Forty participants completed all scheduled study visits. Two-way repeated measures ANOVA showed significant group × time interaction effects for CMJ height (F = 8.858, p = 0.005) and SJ height (F = 6.523, p = 0.015). The interaction effect of the average CJ height of the first 15 s was marginally significant (F = 3.550, p = 0.067). However, there was no significant interaction effect on the Y balance (p > 0.05). Further within-group comparisons showed a significant post-intervention increase in the height of the CMJ (p = 0.004), SJ (p = 0.010) and the average CJ height of the first 15 s (p = 0.004) in the TI group. Conclusion: Repetitive TI stimulation targeting the lower limb motor control area effectively increased vertical jump height in healthy adult males but had no significant effect on dynamic postural stability.

Temporal interference (TI) stimulation is a novel neuromodulation technique that overcomes the depth limitations of traditional transcranial electrical stimulation while avoiding the invasiveness of deep brain stimulation. Our previous behavioral research has demonstrated the effects of multi‐target TI stimulation in enhancing working memory (WM) performance, however, the neural mechanisms of this special form of envelope modulation remain unclear. To address this issue, here we designed this randomized, double‐blind, crossover study, which consisted of a task‐based functional magnetic resonance imaging (fMRI) experiment, to explore how offline TI stimulation modulated brain activity and behavioral performance in healthy adults. We conducted a 2 × 2 within‐subjects design with two factors: stimulation (TI vs. Sham) and time (pre vs. post). Participants received two stimulation protocols in a random order: TI (beat frequency: 6 Hz, targeting middle frontal gyrus [MFG] and inferior parietal lobule [IPL]) and sham stimulation. Neuroimaging data of a WM task with different cognitive loads were acquisited immediately before and after stimulation. We found TI stimulation significantly improved d′ in the high‐demand WM task. Whole‐brain analysis showed the significant time‐by‐stimulation interactions in two main clusters in IPL and precuneus with lower activation after TI stimulation. The generalized psychophysiological interaction (gPPI) analysis revealed a significant interaction in task‐modulated connectivity between MFG and IPL, with improvement observed after TI stimulation. Notably, this increasing functional connectivity induced by TI stimulation was positively correlated with better behavioral performance. Overall, our findings show specific effects of TI stimulation on brain activation and functional connectivity in the frontoparietal network and may contribute to provide new perspectives for future neuromodulation applications.